Anybody wondering about the scale of Louis van Gaal’s rebuilding job at Manchester United had their question answered in stark fashion at Old Trafford yesterday. The crumbling of the old empire under David Moyes last season was writ large by seven home defeats, and Swansea City’s victory yesterday underlined that the old fear factor is not going to return overnight.

Swansea had never won at United prior to January’s triumph in the FA Cup third round, and in repeating the feat yesterday they handed their hosts a first opening-day home loss since 1972.

There were cheeky chants of “You’re getting sacked in the morning” from the away supporters when Swansea took a first half lead through Ki Sung-Yueng, and although Van Gaal’s half-time tactical switch – from three at the back to a back four – prompted an improvement, with Wayne Rooney equalising, Swansea exploited the lack of authority at the heart of this United side with a second goal, from Gylfi Sigurdsson, with 18 minutes remaining.

United had a 100 per cent record in pre-season, but this performance was a more accurate measure of Van Gaal’s task. The evidence of yesterday’s game suggests the only silverware Old Trafford regulars will see this season is the Open trophy that golfer Rory McIlroy (right) displayed at half-time.

With Nemanja Vidic, Patrice Evra and Rio Ferdinand all gone, United lacked leadership at the back, and looked anaemic in midfield, despite the injection of Ander Herrera. “I know in what positions we need better players,” said the Dutchman afterwards and United, who have so far only signed Herrera and Luke Shaw, will have to act fast.

Van Gaal spoke in his programme notes of the sheer size of United – “I always knew this was a big club but it was incredible to witness,” he said of the attendances on their US tour – but yesterday they had the look of a very ordinary team. In mitigation, Van Gaal was missing a notable list of senior players – starting with Robin van Persie and full-back Shaw and running through Antonio Valencia, Jonny Evans, Michael Carrick, Danny Welbeck – and it is worth noting also that first appearances can be deceptive. Moyes beat Swansea in his first game 12 months ago; Sir Alex Ferguson lost at Oxford in his.

Perhaps the biggest positive was Van Gaal’s his willingness to give young players their opportunity. His first line-up featured a goalkeeper and three centre-backs all aged 24 or under – Phil Jones, Chris Smalling and the 20-year-old Tyler Blackett, one of two homegrown debutants along with Jesse Lingard. Lingard occupied a wing-back role on the opposite flank to Ashley Young, yet lasted only 24 minutes before hurting his knee in a challenge with Ashley Williams. Van Gaal suggested afterwards that too many players looked “nervous”, and United’s defending was certainly awry when the South Korean mid-fielder Ki, back at Swansea after a season’s loan at Sunderland, put the visitors ahead with a precise finish after 28 minutes.

Van Gaal was left to reflect on an opening day defeat
He was given too much time and space on the edge of the box and took full advantage, beating De Gea low to the Spaniard’s left.

With United lacking pace and thrust down the flanks, the only first-half save that Swansea’s new goalkeeper, Lukasz Fabianksi, had to make came when Jones came strode forward on a nice interchange with Juan Mata and his attempted cross almost caught out the Pole at his near post. Indeed, two of the biggest cheers of the half came when referee Mike Dean pulled out his can of free-kick vanishing spray.

Rooney fired in a close-range bicycle kick to level the scores
Van Gaal had not stirred from his seat but acted decisively at half-time, sending on Nani for Javier Hernandez and switching from 3-4-2-1 to 4-2-3-1. “[In] the first half we were not playing very well and were behind; that is why I changed the system, and this system they have played always in Manchester United,” he said. Van Gaal praised his players’ effort too, but added that it was important “not only running but also using your brain and then you can play like a team, and in that we have failed today”.

Briefly it looked as though this switch would bear fruit when Rooney equalised with an acrobatic overhead finish after Jones had flicked on Mata’s corner. The new club captain then turned Williams superbly inside the box only to be foiled by an equally good recovering tackle by the Swansea skipper. Rooney came even closer when clipping the outside of the left-hand post with a 20-yard free-kick.

Ki and Sigurdsson celebrated after the final whistle after giving the Swans a memorable victoryInstead Swansea struck with a goal United’s defenders will not enjoy reviewing. Substitute Jefferson Montero got the better of Smalling on the left and crossed to the far post, where Young let the ball drop behind him. Routledge, lurking beyond the far post, drove it back across goal for Sigurdsson to finish.

“Gylfi had a good game, and the way Ashley defended is why he is our captain and our leader, but I cannot single out players because of the effort of the whole team,” said Garry Monk, the Swansea manager. “We limited United to few chances.”

Indeed Swansea might have had a third goal as their substitute Bafe Gomis burst through only to be denied by a last-ditch challenge from Jones.

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